Mannich polyols for rigid spray foams

摘要

Provided herein are polyurethane foams which may be prepared by spray techniques. The foams of the invention are prepared using conventional isocyanates and a novel Mannich condensate polyol having a hydroxy number in the range of 250-340 and a viscosity of 3500 cps or less, and wherein the Mannich condensate polyol is derived from nonylphenol, formaldehyde, an alkanolamine, and propylene oxide as the sole alkoxylating agent. Polyurethane foams prepared according to the invention possess superior physical properties over sprayed polyurethane foams prepared using Mannich condensate polyols which are made using mixtures of propylene oxide and ethylene oxide.